3.7 and 3.8: Mitosis and The cell cycle

Question 1

Mitosis

Answer 1

Produces two daughter cells that have the same number of chromosomes as the parent cell and each other

Question 2

Daughter cells DNA

Answer 2

have an exact copy of the DNA of the parent cell

Question 3

Mutation means

Answer 3

genetic make up of the two daughter nuclei is not identical to that of parent nucleus

Question 4

Interphase

Answer 4

Period that precedes mitosis of cellular activity when the cell isn’t dividing but the replication of DNA is happening.

Question 5

4 stages of mitosis

Answer 5

prophase
metaphase
anaphase
telophase

Question 6

Prophase

stage of mitosis

Answer 6

Chromosomes become visible as two long thin threads, centrioles move to poles of the cell,
spindle fibres develop
nucleolus disappears and nuclear envelope breaks down
chromosomes free in the cytoplasm

Question 7

Centrioles

Answer 7

Organelles where spindle fibres come from

Question 8

Spindle apparatus

Answer 8

spindle fibres collectively

Question 9

Opposite end of the cell

called

Answer 9

Poles

Question 10

Metaphase

Answer 10

Chromosomes made up of two chromatids, the chromatids are joined by the centromere
the chromosomes are pulled along the spindle apparatus and arrange along the equator of the cell

Question 11

Chromatid

Answer 11

each chromatid is an identical copy of DNA from the parent cell

Question 12

Anaphase

Answer 12

the centromeres divide into two
spindle fibres pull the individual chromatids apart
chromatids move to poles and are (chromosomes now)
mitochondria provides energy for the process

Question 13

Telophase

Answer 13

Chromosomes reach their poles
become longer and thinner
then disappear and leave chromatin
spindle fibres disintergrate
nuclear envelope and nucleolus re-form
cytokinesis

Question 14

Cytokinesis

Answer 14

the cytoplasm divides at the end of mitosis

Question 15

Cell division in prokaryotes

Answer 15

binary fission

Question 16

Binary fission

Answer 16

• The circular DNA molecule replicates and both copies attach to the cell membrane
• plasmids also replicate
• the cell membrane begins to grow between the 2 DNA -molecules and begins to pinch inwards,
• cytoplasm divides in 2
• new cell wall forms between the 2 molecules of DNA
• original cell divides into 2 daughter cells

Question 17

Replication of viruses

Answer 17

Can’t undergo cell division
attach to their host cell
inject nucleic acid
genetic info. in nucleic acid provides ‘instructions’ for the cells metabolic processes

Question 18

Some cells don’t divide continuously

Answer 18

undergo the cell cycle

Question 19

Cell cycle

Answer 19

Regulates cycle of division with periods of cell growth

Question 20

Cell cycle

3 stages

Answer 20

interphase
nuclear division
cytokinesis

Question 21

Nuclear division

in cell cycle

Answer 21

when nucleus divides into either 2 (mitosis) or 4 (meiosis)

Question 22

Interphase

in cell cycle

Answer 22

known as resting phase
occupies most of the cell cycle
no cell division occurs